לוח שנה משולב

We introduce a variant of SELEX in-vitro selection to study the evolution of a population of oligonucleotides starting from a seed of random-sequence DNA 50mers (our evolving individuals) and introducing selectivity by an affinity capture gel formed by beads carrying DNA 20mers of fixed sequence that act as targets (our resources). We PCR amplify the captured strands and proceed to the next generation. Because of the simplicity of the process, we could investigate what plays the role of “fitness" in this synthetic evolution process. We find that, across generations, evolution is first driven by the need of binding to the capture gel, while, on a later stages it appear dominated by the emerging of motifs related to inter-individual interactions.

Alzheimer's disease (AD) is a devastating pathology of the central nervous system (CNS) of unknown etiology which represents the most common neurodegenerative disorder. For decades, AD was perceived as a disease of the neuron alone. However, research advances in recent years have challenged this concept and shed light on the critical roles of non-neuronal cells on the development and progression of AD. In my PhD, I focused on understanding how two non-neuronal cell types - the Astrocytes and Microglia - respond to AD and how they possibly affect pathological processes. Our research identified a unique population of Astrocytes that significantly increased in association with brain pathology, which we termed disease-associated astrocytes (DAAs). This novel population of DAAs appeared at an early disease stage, increased in abundance with disease progression, and was not observed in young or in healthy adult animals. In addition, similar astrocytes appeared in aged wild-type (WT) mice and in aging human brains, suggesting their linkage to genetic and age-related factors. Aging is considered the greatest risk factor for AD, although the mechanism underlying the aging-related susceptibility to AD is unknown. One emerging factor that is involved in biological aging is the accumulation of senescent cells. Cellular senescence is a process in which aging cells change their characteristic phenotype. Under physiological conditions senescent cells can be removed by the immune system, however with aging, senescent cells accumulate in tissues, either due to a failure of effective removal or due to the accelerated formation of senescent cells.
Our data highlight the contribution of non neuronal cells to AD pathogenesis by demonstrating  that 1. Overexpression of a specific gene by astrocytes affected the microglia cells' state, leading to a more homeostatic and less reactive microglial phenotype in comparison to the control group. 2. Accumulation of senescent microglia cells was observed in the brain of aged WT mice and AD mouse model (5xFAD), and by applying different therapeutic strategies we managed to observe significant quantitative differences in these cells, followed by a cognitive amelioration.

High-Performance, Rechargeable Li-ion Batteries (LIBs) are key to the global transition from fossil fuels to renewable energy sources. LIBs utilizing lithium metal as the anode are particularly exciting due to their exceptional energy density and redox potential, yet their advancement is hindered by growth of metallic filaments and unstable surface layers. Efficient cationic transport, which is crucial for battery performance, largely depends on the heterogeneous and disordered interphase formed between the anode and the electrolyte during cycling. Directly observing this interphase as well as the dynamic processes involving it is a great challenge. Here we present an approach to elucidate these dynamic processes and correlate them with the corresponding interfacial chemistry, focusing on the first step of cationic transport: surface adsorption. Employing Dark State Exchange Saturation Transfer (DEST) by 7Li NMR, we were able to detect the exchange of Li-ions between the homogenous electrolyte and the heterogeneous surface layer, highlighting the hidden interface between the liquid and solid environments. This enabled determination of the kinetic and energetic binding properties of different surface chemistries, advancing our understanding of cationic transport mechanisms in Li-ion batteries. 

One of the most surprising discoveries in exoplanet science has been the existence of compact systems of Earth to super-Earth sized planets. These multi-planet systems have nearly circular, coplanar orbits located at distances of only ∼ 0.01 − 0.1 AU, a region devoid of planets in our Solar System. Although compact systems comprise a large fraction of known exoplanetary systems, their origin remains debated.
Common to all prior models of compact system origin is the assumption that infall to the stellar disk ends before planets form. However, there is growing observational, theoretical, and meteoritical evidence of the early growth of mm-sized “pebbles” during the infall phase. We propose that accretion of compact systems occurs during stellar infall. As a cloud core collapses, solids are gradually accumulated in the disk, producing favorable conditions for the formation and survival of close-in planets. A key feature of this model is that the reduced gas-to-solids ratio in the planet accretion region can allow for the formation and survival of compact systems, even with Type-I migration.
Accretion within infall-supplied disks has been studied in the context of gas planet satellite origin. Formation models predict that the total mass of the satellite system during this evolution maintains a nearly constant mass ratio ∼10^−4 compared to the host planet’s mass. The maximum mass ratio of compact exoplanetary systems compared to the stellar mass are similar to those of the giant satellite system, suggesting that accretion of compact systems may be similar to regular satellite formation.